PDA

View Full Version : Intercooler , EGR - Projects to Keep detonation under control.



A20A1
09-11-2004, 02:13 AM
I wanted to post this here for a bit to see you guyses input on this...

I was just thinking of turbo applications... though the ratio of usable boost to cold air may not be worth it.

Serious responses/questions only please...

http://www.artxltd.com/vortex/principle.shtml


* This is only an example of the design... the actual part would be proportionate to the intended use.

shepherd79
09-11-2004, 03:28 AM
the question is, how much pressure do you need to to run run on that thing to blow the hot air out.

A20A1
11-29-2005, 05:57 PM
Well any takers? I figure if you hook it to a blow off valve... you may be able to get some cold air to shoot off somewhere.
http://www.exair.com/Cultures/en-US/Primary+Navigation/Products/Vortex+Tubes+and+Spot+Cooling/
shoot' seems you would need a decent supply of CFM and PSI for it to work.
So CO2 may be used but the problem is applying that cold air directly to the core then letting it mix in or dissperse too quicly.
damnit, so close.
I found some nice links to no where.
http://www.studebakerclubs.com/21stCenturyTurbo/Page4_InternetGroups.htm
more stuff
http://www.vs57.com/links.htm
I'ts unfortunate that this requires a fair amount of gas PSI and CFM... one plus is that the pre-turbo Exhaust is at a higher pressure then the intake charge?... but how would you introduce EGR using the vortec as a means of cooling the EGR before it is ingested to help control detonation. or should some other method be used... to cool and injest EGR... or to at the very least make use of the vortex tube.

Here is a diagram I came up with... probably wont work that good but it's a start.

The BOV vents on the hot side of the vortex tube, to help flush out the hot gasses and keep them from building up.

There is a equalizer tube because I figured 'Atmospheric Pressure' is swaped with 'Intake Pipe Pressure' and the pressure at either end of the tube needs to be the same or else the vortex tube may not work right.

There will probably be a few points that will have heat gaskets and spacers to help reduce heat soak from the components.

http://www.3geez.com/forum/attachment.php?attachmentid=4546&d=1133518046

Please respond over...
:)
hehehe
Thubs up, thumbs down?
Not enough pressure difference?
Whats the verdict? :)

Just so you guys know...

This POS is NOT what I'm talking about.
http://www.vortexvalve.com/

Swap_File
12-24-2005, 09:07 PM
(I am editing this post as I find information)

This is basically what you want to do, right?

http://img396.imageshack.us/img396/3258/turbodiagram3ux.jpg
(hacked up picture from http://www.beesandgoats.com/boostfaq/g2icturbo.html)

I think a bigger turbo than normal would be needed because of the hot gas exiting the vortex and not going into the engine. I'm looking at some datasheets but I don't yet know if a useful ammount of cooling would be produced.

If you had a huge vortex tube (I don't know if anything like this exists) you could maybe do this:

http://img514.imageshack.us/img514/641/turbodiagram9qw.jpg

It was said here ( http://www.hotrod.com/techarticles/engine/113_0401_turb/index2.html ) that compressed air going to the intake could be 300 degrees F, and that a good intercooler would drop it to 160F on a 100F day. From here, http://www.synertechnologies.com/pdf_nex_flow/vortex_tubes.pdf best case these vortex tubes would drop the intake temperature 100 F best case through the vortex tube.

For the first picture, that would mean if half of all the air went into the vortex tube, and half of that air came out the cool side, half came out the hot side, we would have a mixture of 1/2 300 F air, 1/4 200 F air, for 266F overall temp going to the engine. (1/4 being exhausted hot from the vortex).

Even if all the air went through the vortex tube like in diagram 2, that would end up with 200 F air going into the intake. (assuming probably better than best case operation)

I made a lot of assumptions and estimations to do these calculations, if something is wrong let me know.

I think the problem with using a vortex tube is that its using the input air itself as a place to distribute the heat to. Vortex tubes seem to be suited for use when you need output temperatures lower than ambient temperatures. An intercooler can just use all the surrounding air to collect the heat.

I also found this about using EGR to reduce knock:
"EGR Theory. EGR serves one purpose and one purpose only. That purpose is to reduce Oxides of Nitrogen (NOx). Undernormal combustion, Nitrogen(N2)Oxygen (O2) in the air and Hydrocarbons (HC) in the fuel combind into water(H2O) Carbon dioxide (CO2) and the Nitrogen remains unchanged. Under very hot combustion temperatures, the Nitrogen reacts with the other two byproducts and forms Nitrogen oxide (NO). After being released into the atmosphere, it picks up another Oxygen and becomes Nitrogen dioxide (NO2). In the presence of sunlight,it combines with other compounds like Hydrocarbons and forms Smog. Since exhaust gas is inert (very stable) it doesn’t burn again. So by being introduced into the combustion chamber, it will lower combustion chamber temps enough so that the Nitrogen doesn’t react with the other compounds and is passed unchanged out the tailpipe thus not contributing to smog. Now, since exhaust gas doesn’t burn, it doesn’t exactly help with combustion. At higher RPM’s, this really isn’t noticable, but at idle, the reintroduction of exhaust gas will cause a very rough idle and can cause stalling if to much is introduced into the combustion chamber "

Sounds to me that since the inert gas is just taking up space in the combustion chamber and not doing anything, you could just as well turn down the boost for similar results. Any comments or ideas? :dunno:

Oh yeah, Nitrogen oxide (NO) is not Nitrous oxide (N2O). I had to double check that one. :)

A20A1
12-24-2005, 11:06 PM
It says it reduces combustion temps.


why not increase boost and run egr? :(

I don't think your diagram shows my setup the way I have it. The vortex tube isn't facing the right way and I think you're missing the pressure equalizing tube I wanted in there, that way you're not using the vortex tube as the sole passageway to equalize pressure on either end of the vortex tube outlets.

Swap_File
12-25-2005, 07:09 AM
I am not quite sure I understand. Could you just edit the picture in paint to show what it should look like? All of this is new to me, I'm just learning as I go.

I did a little more searching, and have seen different things about EGR.

http://72.14.203.104/search?q=cache:ZTFGHDhbY44J:appft1.uspto.gov/netacgi/nph-Parser%3FSect1%3DPTO2%26Sect2%3DHITOFF%26p%3D2%26u %3D%252Fnetahtml%252FPTO%252Fsearch-bool.html%26r%3D52%26f%3DG%26l%3D50%26co1%3DAND%26 d%3DPG01%26s1%3Dcohn.IN.%26OS%3DIN/cohn%26RS%3DIN/cohn+EGR+reduce+knock+on+boosted+engines&hl=en&client=firefox-a

First I saw:

[0003] Engine knock can prevent the use of high compression ratio operation in a spark ignition gasoline engine. Typically, spark ignition gasoline engines are limited to a compression ratio of less than 10.5. Knock is the undesired auto-ignition of unburned fuel and air before it can be burned by the expanding flame front in a spark ignition engine and is exacerbated by high compression ratio operation. Knock at a high compression ratio could be avoided by employing lean operation or dilution from Exhaust Gas Recirculation (EGR). However, the fuel dilution from lean or EGR operation will reduce engine power density (power/cylinder volume).

Then:

[0032] Another mode of operation contemplated herein is to use cooled EGR with stoichiometric or fuel rich, i.e., .lambda. greater than one, operation at high loads. Use of cooled EGR at high loads facilitates higher engine power density operation.

I think I understand what you want to do, would it look something like this?
http://img400.imageshack.us/img400/2967/copyofturbodiagram2ts.jpg

A20A1
08-11-2007, 03:49 AM
yup thats more like it. I dunno if I needed that equalizer tube, it seems ineffective now that I look at it.

One difference is I made the hot end connect to the blow off valve for the intake, but without a free flowing hot end to the vortex tube I don't think it will cool as well so I think it's good the way you have it connecting to the waste gas from the turbo. Also, all this could lead to less exhaust gas to run the turbine so you'll have a less effective turbo.

Also we have to consider cooling the vortex tube itself or shielding it from the input heat of the exhaust or both.

And beyond that will we really get any pressure to get the EGR into the intake or will everything be prone to flush right into the exhaust.

CFM
SCFM - Standard CFM
ACFM - Actual CFM

I think I'm second guessing my second guessing myself... maybe the balance tube is required, and that the hot side should have the BOV, but how to make it so you don't waste boost, I dunno.


Hey on that exair site they sell heavy duty line vac's... more products for electric turbo/SC's fans to draw from.

89T
08-11-2007, 04:40 AM
so is this a replacement for an intercooler?

in one of the earlier posts it is stated that the compressed air can reach 300 deg/100 deg ambiant.

i have watched my iat under boost with the use of a front mount intercooler with only about a 30 degree change in iat and less change verses ambiant with shorter spirt's of boost.

there was a higher degree change when in boost for a long period of time.

i thought i would share some real world experiance with ait's.

I hope this has helped in you'r reserch. (if not you can delete this post.)

A20A1
08-11-2007, 04:42 AM
nope, just a way to cool EGR.